Can anyone please tell the difference between these two AR-15 triggers. They are both from model 1 kits. Pictures below.

Thanks

Quoted: Can anyone please tell the difference between these two AR-15 triggers. They are both from model 1 kits. Pictures below. Thanks us.f2.yahoofs.com/bc/4169dd14_14bed/bc/Pict/ar151.jpg?bfKNeaBBn50b3mvous.f2.yahoofs.com/bc/4169dd14_14bed/bc/Pict/ar152.jpg?bfKNeaBBsboK31otus.f2.yahoofs.com/bc/4169dd14_14bed/bc/Pict/ar153.jpg?bfKNeaBBXqrqfxfius.f2.yahoofs.com/bc/4169dd14_14bed/bc/Pict/ar154.jpg?bfKNeaBBERKa45j4

Not positive, but I think the one on the right started out life as a trigger blank for an M16A2, w/the 3 shot burst parts.  Haven't seen this before on a trigger, but the last hammer I bought was clearly an A2 hammer w/the full auto catch at the back removed.  The disconnactor catch shelf was plainly a 3 shot burst fire, wider, piece though. That would explain the bigger shelf at the front. and the two spring holes.

Remember, Model 1, and most other AR parts sellers, don't make a thing. They simply buy pieces from whoever has what they need at the moment.

Have never seen 2 holes for the disconector spring like that.Usually for a real M16 trigger for the A2 where its a burst feature it will have 2 holes staggered and its a bit wider to hold the 2 disconectors required for the burst function.The notch in the rear I have never seen but it is semi-auto as a full auto trigger would have tis space open for the tail of the full auto disconector.The extra hole could just be a machining mistake as the hole further back is the proper one.Also the rectangular groove forward on the polished sear surface,one seems longer than the other.